Donut is a circular frame folding bicycle concept in which the Handle, saddle, pedals and the wheels folds inside the circular frame with no parts of the bicycle protruding outside the frame. Unlike the existing folding bicycles, which fold about the triangular frame and most of the bicycle parts stick out and make it difficult to carry or stow. The main intention was to design a compact, lightweight folding bicycle, which can be carried in bus/train or[.....]